FFmpeg: libavcodec/mpeg4videodec.c Source File

00001 /*
00002  * MPEG4 decoder.
00003  * Copyright (c) 2000,2001 Fabrice Bellard
00004  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00023 #include "mpegvideo.h"
00024 #include "mpeg4video.h"
00025 #include "h263.h"
00026 #include "thread.h"
00027 
00028 // The defines below define the number of bits that are read at once for
00029 // reading vlc values. Changing these may improve speed and data cache needs
00030 // be aware though that decreasing them may need the number of stages that is
00031 // passed to get_vlc* to be increased.
00032 #define SPRITE_TRAJ_VLC_BITS 6
00033 #define DC_VLC_BITS 9
00034 #define MB_TYPE_B_VLC_BITS 4
00035 
00036 
00037 static VLC dc_lum, dc_chrom;
00038 static VLC sprite_trajectory;
00039 static VLC mb_type_b_vlc;
00040 
00041 static const int mb_type_b_map[4]= {
00042     MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
00043     MB_TYPE_L0L1 | MB_TYPE_16x16,
00044     MB_TYPE_L1 | MB_TYPE_16x16,
00045     MB_TYPE_L0 | MB_TYPE_16x16,
00046 };
00047 
00053 void mpeg4_pred_ac(MpegEncContext * s, DCTELEM *block, int n,
00054                    int dir)
00055 {
00056     int i;
00057     int16_t *ac_val, *ac_val1;
00058     int8_t * const qscale_table= s->current_picture.qscale_table;
00059 
00060     /* find prediction */
00061     ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
00062     ac_val1 = ac_val;
00063     if (s->ac_pred) {
00064         if (dir == 0) {
00065             const int xy= s->mb_x-1 + s->mb_y*s->mb_stride;
00066             /* left prediction */
00067             ac_val -= 16;
00068 
00069             if(s->mb_x==0 || s->qscale == qscale_table[xy] || n==1 || n==3){
00070                 /* same qscale */
00071                 for(i=1;i<8;i++) {
00072                     block[s->dsp.idct_permutation[i<<3]] += ac_val[i];
00073                 }
00074             }else{
00075                 /* different qscale, we must rescale */
00076                 for(i=1;i<8;i++) {
00077                     block[s->dsp.idct_permutation[i<<3]] += ROUNDED_DIV(ac_val[i]*qscale_table[xy], s->qscale);
00078                 }
00079             }
00080         } else {
00081             const int xy= s->mb_x + s->mb_y*s->mb_stride - s->mb_stride;
00082             /* top prediction */
00083             ac_val -= 16 * s->block_wrap[n];
00084 
00085             if(s->mb_y==0 || s->qscale == qscale_table[xy] || n==2 || n==3){
00086                 /* same qscale */
00087                 for(i=1;i<8;i++) {
00088                     block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
00089                 }
00090             }else{
00091                 /* different qscale, we must rescale */
00092                 for(i=1;i<8;i++) {
00093                     block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8]*qscale_table[xy], s->qscale);
00094                 }
00095             }
00096         }
00097     }
00098     /* left copy */
00099     for(i=1;i<8;i++)
00100         ac_val1[i    ] = block[s->dsp.idct_permutation[i<<3]];
00101 
00102     /* top copy */
00103     for(i=1;i<8;i++)
00104         ac_val1[8 + i] = block[s->dsp.idct_permutation[i   ]];
00105 
00106 }
00107 
00112 static inline int mpeg4_is_resync(MpegEncContext *s){
00113     int bits_count= get_bits_count(&s->gb);
00114     int v= show_bits(&s->gb, 16);
00115 
00116     if(s->workaround_bugs&FF_BUG_NO_PADDING){
00117         return 0;
00118     }
00119 
00120     while(v<=0xFF){
00121         if(s->pict_type==AV_PICTURE_TYPE_B || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
00122             break;
00123         skip_bits(&s->gb, 8+s->pict_type);
00124         bits_count+= 8+s->pict_type;
00125         v= show_bits(&s->gb, 16);
00126     }
00127 
00128     if(bits_count + 8 >= s->gb.size_in_bits){
00129         v>>=8;
00130         v|= 0x7F >> (7-(bits_count&7));
00131 
00132         if(v==0x7F)
00133             return 1;
00134     }else{
00135         if(v == ff_mpeg4_resync_prefix[bits_count&7]){
00136             int len;
00137             GetBitContext gb= s->gb;
00138 
00139             skip_bits(&s->gb, 1);
00140             align_get_bits(&s->gb);
00141 
00142             for(len=0; len<32; len++){
00143                 if(get_bits1(&s->gb)) break;
00144             }
00145 
00146             s->gb= gb;
00147 
00148             if(len>=ff_mpeg4_get_video_packet_prefix_length(s))
00149                 return 1;
00150         }
00151     }
00152     return 0;
00153 }
00154 
00155 static void mpeg4_decode_sprite_trajectory(MpegEncContext * s, GetBitContext *gb)
00156 {
00157     int i;
00158     int a= 2<<s->sprite_warping_accuracy;
00159     int rho= 3-s->sprite_warping_accuracy;
00160     int r=16/a;
00161     const int vop_ref[4][2]= {{0,0}, {s->width,0}, {0, s->height}, {s->width, s->height}}; // only true for rectangle shapes
00162     int d[4][2]={{0,0}, {0,0}, {0,0}, {0,0}};
00163     int sprite_ref[4][2];
00164     int virtual_ref[2][2];
00165     int w2, h2, w3, h3;
00166     int alpha=0, beta=0;
00167     int w= s->width;
00168     int h= s->height;
00169     int min_ab;
00170 
00171     for(i=0; i<s->num_sprite_warping_points; i++){
00172         int length;
00173         int x=0, y=0;
00174 
00175         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
00176         if(length){
00177             x= get_xbits(gb, length);
00178         }
00179         if(!(s->divx_version==500 && s->divx_build==413)) skip_bits1(gb); /* marker bit */
00180 
00181         length= get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
00182         if(length){
00183             y=get_xbits(gb, length);
00184         }
00185         skip_bits1(gb); /* marker bit */
00186         s->sprite_traj[i][0]= d[i][0]= x;
00187         s->sprite_traj[i][1]= d[i][1]= y;
00188     }
00189     for(; i<4; i++)
00190         s->sprite_traj[i][0]= s->sprite_traj[i][1]= 0;
00191 
00192     while((1<<alpha)<w) alpha++;
00193     while((1<<beta )<h) beta++; // there seems to be a typo in the mpeg4 std for the definition of w' and h'
00194     w2= 1<<alpha;
00195     h2= 1<<beta;
00196 
00197 // Note, the 4th point isn't used for GMC
00198     if(s->divx_version==500 && s->divx_build==413){
00199         sprite_ref[0][0]= a*vop_ref[0][0] + d[0][0];
00200         sprite_ref[0][1]= a*vop_ref[0][1] + d[0][1];
00201         sprite_ref[1][0]= a*vop_ref[1][0] + d[0][0] + d[1][0];
00202         sprite_ref[1][1]= a*vop_ref[1][1] + d[0][1] + d[1][1];
00203         sprite_ref[2][0]= a*vop_ref[2][0] + d[0][0] + d[2][0];
00204         sprite_ref[2][1]= a*vop_ref[2][1] + d[0][1] + d[2][1];
00205     } else {
00206         sprite_ref[0][0]= (a>>1)*(2*vop_ref[0][0] + d[0][0]);
00207         sprite_ref[0][1]= (a>>1)*(2*vop_ref[0][1] + d[0][1]);
00208         sprite_ref[1][0]= (a>>1)*(2*vop_ref[1][0] + d[0][0] + d[1][0]);
00209         sprite_ref[1][1]= (a>>1)*(2*vop_ref[1][1] + d[0][1] + d[1][1]);
00210         sprite_ref[2][0]= (a>>1)*(2*vop_ref[2][0] + d[0][0] + d[2][0]);
00211         sprite_ref[2][1]= (a>>1)*(2*vop_ref[2][1] + d[0][1] + d[2][1]);
00212     }
00213 /*    sprite_ref[3][0]= (a>>1)*(2*vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
00214     sprite_ref[3][1]= (a>>1)*(2*vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */
00215 
00216 // this is mostly identical to the mpeg4 std (and is totally unreadable because of that ...)
00217 // perhaps it should be reordered to be more readable ...
00218 // the idea behind this virtual_ref mess is to be able to use shifts later per pixel instead of divides
00219 // so the distance between points is converted from w&h based to w2&h2 based which are of the 2^x form
00220     virtual_ref[0][0]= 16*(vop_ref[0][0] + w2)
00221         + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + w2*(r*sprite_ref[1][0] - 16*vop_ref[1][0])),w);
00222     virtual_ref[0][1]= 16*vop_ref[0][1]
00223         + ROUNDED_DIV(((w - w2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + w2*(r*sprite_ref[1][1] - 16*vop_ref[1][1])),w);
00224     virtual_ref[1][0]= 16*vop_ref[0][0]
00225         + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][0] - 16*vop_ref[0][0]) + h2*(r*sprite_ref[2][0] - 16*vop_ref[2][0])),h);
00226     virtual_ref[1][1]= 16*(vop_ref[0][1] + h2)
00227         + ROUNDED_DIV(((h - h2)*(r*sprite_ref[0][1] - 16*vop_ref[0][1]) + h2*(r*sprite_ref[2][1] - 16*vop_ref[2][1])),h);
00228 
00229     switch(s->num_sprite_warping_points)
00230     {
00231         case 0:
00232             s->sprite_offset[0][0]= 0;
00233             s->sprite_offset[0][1]= 0;
00234             s->sprite_offset[1][0]= 0;
00235             s->sprite_offset[1][1]= 0;
00236             s->sprite_delta[0][0]= a;
00237             s->sprite_delta[0][1]= 0;
00238             s->sprite_delta[1][0]= 0;
00239             s->sprite_delta[1][1]= a;
00240             s->sprite_shift[0]= 0;
00241             s->sprite_shift[1]= 0;
00242             break;
00243         case 1: //GMC only
00244             s->sprite_offset[0][0]= sprite_ref[0][0] - a*vop_ref[0][0];
00245             s->sprite_offset[0][1]= sprite_ref[0][1] - a*vop_ref[0][1];
00246             s->sprite_offset[1][0]= ((sprite_ref[0][0]>>1)|(sprite_ref[0][0]&1)) - a*(vop_ref[0][0]/2);
00247             s->sprite_offset[1][1]= ((sprite_ref[0][1]>>1)|(sprite_ref[0][1]&1)) - a*(vop_ref[0][1]/2);
00248             s->sprite_delta[0][0]= a;
00249             s->sprite_delta[0][1]= 0;
00250             s->sprite_delta[1][0]= 0;
00251             s->sprite_delta[1][1]= a;
00252             s->sprite_shift[0]= 0;
00253             s->sprite_shift[1]= 0;
00254             break;
00255         case 2:
00256             s->sprite_offset[0][0]= (sprite_ref[0][0]<<(alpha+rho))
00257                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][0])
00258                                                   + ( r*sprite_ref[0][1] - virtual_ref[0][1])*(-vop_ref[0][1])
00259                                                   + (1<<(alpha+rho-1));
00260             s->sprite_offset[0][1]= (sprite_ref[0][1]<<(alpha+rho))
00261                                                   + (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-vop_ref[0][0])
00262                                                   + (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-vop_ref[0][1])
00263                                                   + (1<<(alpha+rho-1));
00264             s->sprite_offset[1][0]= ( (-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][0] + 1)
00265                                      +( r*sprite_ref[0][1] - virtual_ref[0][1])*(-2*vop_ref[0][1] + 1)
00266                                      +2*w2*r*sprite_ref[0][0]
00267                                      - 16*w2
00268                                      + (1<<(alpha+rho+1)));
00269             s->sprite_offset[1][1]= ( (-r*sprite_ref[0][1] + virtual_ref[0][1])*(-2*vop_ref[0][0] + 1)
00270                                      +(-r*sprite_ref[0][0] + virtual_ref[0][0])*(-2*vop_ref[0][1] + 1)
00271                                      +2*w2*r*sprite_ref[0][1]
00272                                      - 16*w2
00273                                      + (1<<(alpha+rho+1)));
00274             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
00275             s->sprite_delta[0][1]=   (+r*sprite_ref[0][1] - virtual_ref[0][1]);
00276             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1]);
00277             s->sprite_delta[1][1]=   (-r*sprite_ref[0][0] + virtual_ref[0][0]);
00278 
00279             s->sprite_shift[0]= alpha+rho;
00280             s->sprite_shift[1]= alpha+rho+2;
00281             break;
00282         case 3:
00283             min_ab= FFMIN(alpha, beta);
00284             w3= w2>>min_ab;
00285             h3= h2>>min_ab;
00286             s->sprite_offset[0][0]=  (sprite_ref[0][0]<<(alpha+beta+rho-min_ab))
00287                                    + (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-vop_ref[0][0])
00288                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-vop_ref[0][1])
00289                                    + (1<<(alpha+beta+rho-min_ab-1));
00290             s->sprite_offset[0][1]=  (sprite_ref[0][1]<<(alpha+beta+rho-min_ab))
00291                                    + (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-vop_ref[0][0])
00292                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-vop_ref[0][1])
00293                                    + (1<<(alpha+beta+rho-min_ab-1));
00294             s->sprite_offset[1][0]=  (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3*(-2*vop_ref[0][0] + 1)
00295                                    + (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3*(-2*vop_ref[0][1] + 1)
00296                                    + 2*w2*h3*r*sprite_ref[0][0]
00297                                    - 16*w2*h3
00298                                    + (1<<(alpha+beta+rho-min_ab+1));
00299             s->sprite_offset[1][1]=  (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3*(-2*vop_ref[0][0] + 1)
00300                                    + (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3*(-2*vop_ref[0][1] + 1)
00301                                    + 2*w2*h3*r*sprite_ref[0][1]
00302                                    - 16*w2*h3
00303                                    + (1<<(alpha+beta+rho-min_ab+1));
00304             s->sprite_delta[0][0]=   (-r*sprite_ref[0][0] + virtual_ref[0][0])*h3;
00305             s->sprite_delta[0][1]=   (-r*sprite_ref[0][0] + virtual_ref[1][0])*w3;
00306             s->sprite_delta[1][0]=   (-r*sprite_ref[0][1] + virtual_ref[0][1])*h3;
00307             s->sprite_delta[1][1]=   (-r*sprite_ref[0][1] + virtual_ref[1][1])*w3;
00308 
00309             s->sprite_shift[0]= alpha + beta + rho - min_ab;
00310             s->sprite_shift[1]= alpha + beta + rho - min_ab + 2;
00311             break;
00312     }
00313     /* try to simplify the situation */
00314     if(   s->sprite_delta[0][0] == a<<s->sprite_shift[0]
00315        && s->sprite_delta[0][1] == 0
00316        && s->sprite_delta[1][0] == 0
00317        && s->sprite_delta[1][1] == a<<s->sprite_shift[0])
00318     {
00319         s->sprite_offset[0][0]>>=s->sprite_shift[0];
00320         s->sprite_offset[0][1]>>=s->sprite_shift[0];
00321         s->sprite_offset[1][0]>>=s->sprite_shift[1];
00322         s->sprite_offset[1][1]>>=s->sprite_shift[1];
00323         s->sprite_delta[0][0]= a;
00324         s->sprite_delta[0][1]= 0;
00325         s->sprite_delta[1][0]= 0;
00326         s->sprite_delta[1][1]= a;
00327         s->sprite_shift[0]= 0;
00328         s->sprite_shift[1]= 0;
00329         s->real_sprite_warping_points=1;
00330     }
00331     else{
00332         int shift_y= 16 - s->sprite_shift[0];
00333         int shift_c= 16 - s->sprite_shift[1];
00334         for(i=0; i<2; i++){
00335             s->sprite_offset[0][i]<<= shift_y;
00336             s->sprite_offset[1][i]<<= shift_c;
00337             s->sprite_delta[0][i]<<= shift_y;
00338             s->sprite_delta[1][i]<<= shift_y;
00339             s->sprite_shift[i]= 16;
00340         }
00341         s->real_sprite_warping_points= s->num_sprite_warping_points;
00342     }
00343 }
00344 
00349 int mpeg4_decode_video_packet_header(MpegEncContext *s)
00350 {
00351     int mb_num_bits= av_log2(s->mb_num - 1) + 1;
00352     int header_extension=0, mb_num, len;
00353 
00354     /* is there enough space left for a video packet + header */
00355     if( get_bits_count(&s->gb) > s->gb.size_in_bits-20) return -1;
00356 
00357     for(len=0; len<32; len++){
00358         if(get_bits1(&s->gb)) break;
00359     }
00360 
00361     if(len!=ff_mpeg4_get_video_packet_prefix_length(s)){
00362         av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
00363         return -1;
00364     }
00365 
00366     if(s->shape != RECT_SHAPE){
00367         header_extension= get_bits1(&s->gb);
00368         //FIXME more stuff here
00369     }
00370 
00371     mb_num= get_bits(&s->gb, mb_num_bits);
00372     if(mb_num>=s->mb_num){
00373         av_log(s->avctx, AV_LOG_ERROR, "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
00374         return -1;
00375     }
00376     if(s->pict_type == AV_PICTURE_TYPE_B){
00377         int mb_x = 0, mb_y = 0;
00378 
00379         while(s->next_picture.mbskip_table[ s->mb_index2xy[ mb_num ] ]) {
00380             if (!mb_x) ff_thread_await_progress((AVFrame*)s->next_picture_ptr, mb_y++, 0);
00381             mb_num++;
00382             if (++mb_x == s->mb_width) mb_x = 0;
00383         }
00384         if(mb_num >= s->mb_num) return -1; // slice contains just skipped MBs which where already decoded
00385     }
00386 
00387     s->mb_x= mb_num % s->mb_width;
00388     s->mb_y= mb_num / s->mb_width;
00389 
00390     if(s->shape != BIN_ONLY_SHAPE){
00391         int qscale= get_bits(&s->gb, s->quant_precision);
00392         if(qscale)
00393             s->chroma_qscale=s->qscale= qscale;
00394     }
00395 
00396     if(s->shape == RECT_SHAPE){
00397         header_extension= get_bits1(&s->gb);
00398     }
00399     if(header_extension){
00400         int time_incr=0;
00401 
00402         while (get_bits1(&s->gb) != 0)
00403             time_incr++;
00404 
00405         check_marker(&s->gb, "before time_increment in video packed header");
00406         skip_bits(&s->gb, s->time_increment_bits); /* time_increment */
00407         check_marker(&s->gb, "before vop_coding_type in video packed header");
00408 
00409         skip_bits(&s->gb, 2); /* vop coding type */
00410         //FIXME not rect stuff here
00411 
00412         if(s->shape != BIN_ONLY_SHAPE){
00413             skip_bits(&s->gb, 3); /* intra dc vlc threshold */
00414 //FIXME don't just ignore everything
00415             if(s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
00416                 mpeg4_decode_sprite_trajectory(s, &s->gb);
00417                 av_log(s->avctx, AV_LOG_ERROR, "untested\n");
00418             }
00419 
00420             //FIXME reduced res stuff here
00421 
00422             if (s->pict_type != AV_PICTURE_TYPE_I) {
00423                 int f_code = get_bits(&s->gb, 3);       /* fcode_for */
00424                 if(f_code==0){
00425                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (f_code=0)\n");
00426                 }
00427             }
00428             if (s->pict_type == AV_PICTURE_TYPE_B) {
00429                 int b_code = get_bits(&s->gb, 3);
00430                 if(b_code==0){
00431                     av_log(s->avctx, AV_LOG_ERROR, "Error, video packet header damaged (b_code=0)\n");
00432                 }
00433             }
00434         }
00435     }
00436     //FIXME new-pred stuff
00437 
00438     return 0;
00439 }
00440 
00446 static inline int get_amv(MpegEncContext *s, int n){
00447     int x, y, mb_v, sum, dx, dy, shift;
00448     int len = 1 << (s->f_code + 4);
00449     const int a= s->sprite_warping_accuracy;
00450 
00451     if(s->workaround_bugs & FF_BUG_AMV)
00452         len >>= s->quarter_sample;
00453 
00454     if(s->real_sprite_warping_points==1){
00455         if(s->divx_version==500 && s->divx_build==413)
00456             sum= s->sprite_offset[0][n] / (1<<(a - s->quarter_sample));
00457         else
00458             sum= RSHIFT(s->sprite_offset[0][n]<<s->quarter_sample, a);
00459     }else{
00460         dx= s->sprite_delta[n][0];
00461         dy= s->sprite_delta[n][1];
00462         shift= s->sprite_shift[0];
00463         if(n) dy -= 1<<(shift + a + 1);
00464         else  dx -= 1<<(shift + a + 1);
00465         mb_v= s->sprite_offset[0][n] + dx*s->mb_x*16 + dy*s->mb_y*16;
00466 
00467         sum=0;
00468         for(y=0; y<16; y++){
00469             int v;
00470 
00471             v= mb_v + dy*y;
00472             //XXX FIXME optimize
00473             for(x=0; x<16; x++){
00474                 sum+= v>>shift;
00475                 v+= dx;
00476             }
00477         }
00478         sum= RSHIFT(sum, a+8-s->quarter_sample);
00479     }
00480 
00481     if      (sum < -len) sum= -len;
00482     else if (sum >= len) sum= len-1;
00483 
00484     return sum;
00485 }
00486 
00493 static inline int mpeg4_decode_dc(MpegEncContext * s, int n, int *dir_ptr)
00494 {
00495     int level, code;
00496 
00497     if (n < 4)
00498         code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
00499     else
00500         code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
00501     if (code < 0 || code > 9 /* && s->nbit<9 */){
00502         av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
00503         return -1;
00504     }
00505     if (code == 0) {
00506         level = 0;
00507     } else {
00508         if(IS_3IV1){
00509             if(code==1)
00510                 level= 2*get_bits1(&s->gb)-1;
00511             else{
00512                 if(get_bits1(&s->gb))
00513                     level = get_bits(&s->gb, code-1) + (1<<(code-1));
00514                 else
00515                     level = -get_bits(&s->gb, code-1) - (1<<(code-1));
00516             }
00517         }else{
00518             level = get_xbits(&s->gb, code);
00519         }
00520 
00521         if (code > 8){
00522             if(get_bits1(&s->gb)==0){ /* marker */
00523                 if(s->error_recognition>=2){
00524                     av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
00525                     return -1;
00526                 }
00527             }
00528         }
00529     }
00530 
00531     return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
00532 }
00533 
00538 static int mpeg4_decode_partition_a(MpegEncContext *s){
00539     int mb_num;
00540     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
00541 
00542     /* decode first partition */
00543     mb_num=0;
00544     s->first_slice_line=1;
00545     for(; s->mb_y<s->mb_height; s->mb_y++){
00546         ff_init_block_index(s);
00547         for(; s->mb_x<s->mb_width; s->mb_x++){
00548             const int xy= s->mb_x + s->mb_y*s->mb_stride;
00549             int cbpc;
00550             int dir=0;
00551 
00552             mb_num++;
00553             ff_update_block_index(s);
00554             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
00555                 s->first_slice_line=0;
00556 
00557             if(s->pict_type==AV_PICTURE_TYPE_I){
00558                 int i;
00559 
00560                 do{
00561                     if(show_bits_long(&s->gb, 19)==DC_MARKER){
00562                         return mb_num-1;
00563                     }
00564 
00565                     cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
00566                     if (cbpc < 0){
00567                         av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
00568                         return -1;
00569                     }
00570                 }while(cbpc == 8);
00571 
00572                 s->cbp_table[xy]= cbpc & 3;
00573                 s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
00574                 s->mb_intra = 1;
00575 
00576                 if(cbpc & 4) {
00577                     ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00578                 }
00579                 s->current_picture.qscale_table[xy]= s->qscale;
00580 
00581                 s->mbintra_table[xy]= 1;
00582                 for(i=0; i<6; i++){
00583                     int dc_pred_dir;
00584                     int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
00585                     if(dc < 0){
00586                         av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
00587                         return -1;
00588                     }
00589                     dir<<=1;
00590                     if(dc_pred_dir) dir|=1;
00591                 }
00592                 s->pred_dir_table[xy]= dir;
00593             }else{ /* P/S_TYPE */
00594                 int mx, my, pred_x, pred_y, bits;
00595                 int16_t * const mot_val= s->current_picture.motion_val[0][s->block_index[0]];
00596                 const int stride= s->b8_stride*2;
00597 
00598 try_again:
00599                 bits= show_bits(&s->gb, 17);
00600                 if(bits==MOTION_MARKER){
00601                     return mb_num-1;
00602                 }
00603                 skip_bits1(&s->gb);
00604                 if(bits&0x10000){
00605                     /* skip mb */
00606                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
00607                         s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
00608                         mx= get_amv(s, 0);
00609                         my= get_amv(s, 1);
00610                     }else{
00611                         s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
00612                         mx=my=0;
00613                     }
00614                     mot_val[0       ]= mot_val[2       ]=
00615                     mot_val[0+stride]= mot_val[2+stride]= mx;
00616                     mot_val[1       ]= mot_val[3       ]=
00617                     mot_val[1+stride]= mot_val[3+stride]= my;
00618 
00619                     if(s->mbintra_table[xy])
00620                         ff_clean_intra_table_entries(s);
00621                     continue;
00622                 }
00623 
00624                 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
00625                 if (cbpc < 0){
00626                     av_log(s->avctx, AV_LOG_ERROR, "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
00627                     return -1;
00628                 }
00629                 if(cbpc == 20)
00630                     goto try_again;
00631 
00632                 s->cbp_table[xy]= cbpc&(8+3); //8 is dquant
00633 
00634                 s->mb_intra = ((cbpc & 4) != 0);
00635 
00636                 if(s->mb_intra){
00637                     s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
00638                     s->mbintra_table[xy]= 1;
00639                     mot_val[0       ]= mot_val[2       ]=
00640                     mot_val[0+stride]= mot_val[2+stride]= 0;
00641                     mot_val[1       ]= mot_val[3       ]=
00642                     mot_val[1+stride]= mot_val[3+stride]= 0;
00643                 }else{
00644                     if(s->mbintra_table[xy])
00645                         ff_clean_intra_table_entries(s);
00646 
00647                     if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
00648                         s->mcsel= get_bits1(&s->gb);
00649                     else s->mcsel= 0;
00650 
00651                     if ((cbpc & 16) == 0) {
00652                         /* 16x16 motion prediction */
00653 
00654                         h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
00655                         if(!s->mcsel){
00656                             mx = h263_decode_motion(s, pred_x, s->f_code);
00657                             if (mx >= 0xffff)
00658                                 return -1;
00659 
00660                             my = h263_decode_motion(s, pred_y, s->f_code);
00661                             if (my >= 0xffff)
00662                                 return -1;
00663                             s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
00664                         } else {
00665                             mx = get_amv(s, 0);
00666                             my = get_amv(s, 1);
00667                             s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_GMC | MB_TYPE_L0;
00668                         }
00669 
00670                         mot_val[0       ]= mot_val[2       ] =
00671                         mot_val[0+stride]= mot_val[2+stride]= mx;
00672                         mot_val[1       ]= mot_val[3       ]=
00673                         mot_val[1+stride]= mot_val[3+stride]= my;
00674                     } else {
00675                         int i;
00676                         s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0;
00677                         for(i=0;i<4;i++) {
00678                             int16_t *mot_val= h263_pred_motion(s, i, 0, &pred_x, &pred_y);
00679                             mx = h263_decode_motion(s, pred_x, s->f_code);
00680                             if (mx >= 0xffff)
00681                                 return -1;
00682 
00683                             my = h263_decode_motion(s, pred_y, s->f_code);
00684                             if (my >= 0xffff)
00685                                 return -1;
00686                             mot_val[0] = mx;
00687                             mot_val[1] = my;
00688                         }
00689                     }
00690                 }
00691             }
00692         }
00693         s->mb_x= 0;
00694     }
00695 
00696     return mb_num;
00697 }
00698 
00703 static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count){
00704     int mb_num=0;
00705     static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
00706 
00707     s->mb_x= s->resync_mb_x;
00708     s->first_slice_line=1;
00709     for(s->mb_y= s->resync_mb_y; mb_num < mb_count; s->mb_y++){
00710         ff_init_block_index(s);
00711         for(; mb_num < mb_count && s->mb_x<s->mb_width; s->mb_x++){
00712             const int xy= s->mb_x + s->mb_y*s->mb_stride;
00713 
00714             mb_num++;
00715             ff_update_block_index(s);
00716             if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1)
00717                 s->first_slice_line=0;
00718 
00719             if(s->pict_type==AV_PICTURE_TYPE_I){
00720                 int ac_pred= get_bits1(&s->gb);
00721                 int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00722                 if(cbpy<0){
00723                     av_log(s->avctx, AV_LOG_ERROR, "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00724                     return -1;
00725                 }
00726 
00727                 s->cbp_table[xy]|= cbpy<<2;
00728                 s->current_picture.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
00729             }else{ /* P || S_TYPE */
00730                 if(IS_INTRA(s->current_picture.mb_type[xy])){
00731                     int dir=0,i;
00732                     int ac_pred = get_bits1(&s->gb);
00733                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00734 
00735                     if(cbpy<0){
00736                         av_log(s->avctx, AV_LOG_ERROR, "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00737                         return -1;
00738                     }
00739 
00740                     if(s->cbp_table[xy] & 8) {
00741                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00742                     }
00743                     s->current_picture.qscale_table[xy]= s->qscale;
00744 
00745                     for(i=0; i<6; i++){
00746                         int dc_pred_dir;
00747                         int dc= mpeg4_decode_dc(s, i, &dc_pred_dir);
00748                         if(dc < 0){
00749                             av_log(s->avctx, AV_LOG_ERROR, "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
00750                             return -1;
00751                         }
00752                         dir<<=1;
00753                         if(dc_pred_dir) dir|=1;
00754                     }
00755                     s->cbp_table[xy]&= 3; //remove dquant
00756                     s->cbp_table[xy]|= cbpy<<2;
00757                     s->current_picture.mb_type[xy] |= ac_pred*MB_TYPE_ACPRED;
00758                     s->pred_dir_table[xy]= dir;
00759                 }else if(IS_SKIP(s->current_picture.mb_type[xy])){
00760                     s->current_picture.qscale_table[xy]= s->qscale;
00761                     s->cbp_table[xy]= 0;
00762                 }else{
00763                     int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
00764 
00765                     if(cbpy<0){
00766                         av_log(s->avctx, AV_LOG_ERROR, "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
00767                         return -1;
00768                     }
00769 
00770                     if(s->cbp_table[xy] & 8) {
00771                         ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
00772                     }
00773                     s->current_picture.qscale_table[xy]= s->qscale;
00774 
00775                     s->cbp_table[xy]&= 3; //remove dquant
00776                     s->cbp_table[xy]|= (cbpy^0xf)<<2;
00777                 }
00778             }
00779         }
00780         if(mb_num >= mb_count) return 0;
00781         s->mb_x= 0;
00782     }
00783     return 0;
00784 }
00785 
00790 int ff_mpeg4_decode_partitions(MpegEncContext *s)
00791 {
00792     int mb_num;
00793     const int part_a_error= s->pict_type==AV_PICTURE_TYPE_I ? (DC_ERROR|MV_ERROR) : MV_ERROR;
00794     const int part_a_end  = s->pict_type==AV_PICTURE_TYPE_I ? (DC_END  |MV_END)   : MV_END;
00795 
00796     mb_num= mpeg4_decode_partition_a(s);
00797     if(mb_num<0){
00798         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
00799         return -1;
00800     }
00801 
00802     if(s->resync_mb_x + s->resync_mb_y*s->mb_width + mb_num > s->mb_num){
00803         av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
00804         ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, part_a_error);
00805         return -1;
00806     }
00807 
00808     s->mb_num_left= mb_num;
00809 
00810     if(s->pict_type==AV_PICTURE_TYPE_I){
00811         while(show_bits(&s->gb, 9) == 1)
00812             skip_bits(&s->gb, 9);
00813         if(get_bits_long(&s->gb, 19)!=DC_MARKER){
00814             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first I partition at %d %d\n", s->mb_x, s->mb_y);
00815             return -1;
00816         }
00817     }else{
00818         while(show_bits(&s->gb, 10) == 1)
00819             skip_bits(&s->gb, 10);
00820         if(get_bits(&s->gb, 17)!=MOTION_MARKER){
00821             av_log(s->avctx, AV_LOG_ERROR, "marker missing after first P partition at %d %d\n", s->mb_x, s->mb_y);
00822             return -1;
00823         }
00824     }
00825     ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, part_a_end);
00826 
00827     if( mpeg4_decode_partition_b(s, mb_num) < 0){
00828         if(s->pict_type==AV_PICTURE_TYPE_P)
00829             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, DC_ERROR);
00830         return -1;
00831     }else{
00832         if(s->pict_type==AV_PICTURE_TYPE_P)
00833             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, DC_END);
00834     }
00835 
00836     return 0;
00837 }
00838 
00843 static inline int mpeg4_decode_block(MpegEncContext * s, DCTELEM * block,
00844                               int n, int coded, int intra, int rvlc)
00845 {
00846     int level, i, last, run;
00847     int dc_pred_dir;
00848     RLTable * rl;
00849     RL_VLC_ELEM * rl_vlc;
00850     const uint8_t * scan_table;
00851     int qmul, qadd;
00852 
00853     //Note intra & rvlc should be optimized away if this is inlined
00854 
00855     if(intra) {
00856       if(s->use_intra_dc_vlc){
00857         /* DC coef */
00858         if(s->partitioned_frame){
00859             level = s->dc_val[0][ s->block_index[n] ];
00860             if(n<4) level= FASTDIV((level + (s->y_dc_scale>>1)), s->y_dc_scale);
00861             else    level= FASTDIV((level + (s->c_dc_scale>>1)), s->c_dc_scale);
00862             dc_pred_dir= (s->pred_dir_table[s->mb_x + s->mb_y*s->mb_stride]<<n)&32;
00863         }else{
00864             level = mpeg4_decode_dc(s, n, &dc_pred_dir);
00865             if (level < 0)
00866                 return -1;
00867         }
00868         block[0] = level;
00869         i = 0;
00870       }else{
00871             i = -1;
00872             ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
00873       }
00874       if (!coded)
00875           goto not_coded;
00876 
00877       if(rvlc){
00878           rl = &rvlc_rl_intra;
00879           rl_vlc = rvlc_rl_intra.rl_vlc[0];
00880       }else{
00881           rl = &ff_mpeg4_rl_intra;
00882           rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
00883       }
00884       if (s->ac_pred) {
00885           if (dc_pred_dir == 0)
00886               scan_table = s->intra_v_scantable.permutated; /* left */
00887           else
00888               scan_table = s->intra_h_scantable.permutated; /* top */
00889       } else {
00890             scan_table = s->intra_scantable.permutated;
00891       }
00892       qmul=1;
00893       qadd=0;
00894     } else {
00895         i = -1;
00896         if (!coded) {
00897             s->block_last_index[n] = i;
00898             return 0;
00899         }
00900         if(rvlc) rl = &rvlc_rl_inter;
00901         else     rl = &ff_h263_rl_inter;
00902 
00903         scan_table = s->intra_scantable.permutated;
00904 
00905         if(s->mpeg_quant){
00906             qmul=1;
00907             qadd=0;
00908             if(rvlc){
00909                 rl_vlc = rvlc_rl_inter.rl_vlc[0];
00910             }else{
00911                 rl_vlc = ff_h263_rl_inter.rl_vlc[0];
00912             }
00913         }else{
00914             qmul = s->qscale << 1;
00915             qadd = (s->qscale - 1) | 1;
00916             if(rvlc){
00917                 rl_vlc = rvlc_rl_inter.rl_vlc[s->qscale];
00918             }else{
00919                 rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
00920             }
00921         }
00922     }
00923   {
00924     OPEN_READER(re, &s->gb);
00925     for(;;) {
00926         UPDATE_CACHE(re, &s->gb);
00927         GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
00928         if (level==0) {
00929           /* escape */
00930           if(rvlc){
00931                 if(SHOW_UBITS(re, &s->gb, 1)==0){
00932                     av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in rvlc esc\n");
00933                     return -1;
00934                 }; SKIP_CACHE(re, &s->gb, 1);
00935 
00936                 last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
00937                 run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
00938                 SKIP_COUNTER(re, &s->gb, 1+1+6);
00939                 UPDATE_CACHE(re, &s->gb);
00940 
00941                 if(SHOW_UBITS(re, &s->gb, 1)==0){
00942                     av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in rvlc esc\n");
00943                     return -1;
00944                 }; SKIP_CACHE(re, &s->gb, 1);
00945 
00946                 level= SHOW_UBITS(re, &s->gb, 11); SKIP_CACHE(re, &s->gb, 11);
00947 
00948                 if(SHOW_UBITS(re, &s->gb, 5)!=0x10){
00949                     av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
00950                     return -1;
00951                 }; SKIP_CACHE(re, &s->gb, 5);
00952 
00953                 level=  level * qmul + qadd;
00954                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1); LAST_SKIP_CACHE(re, &s->gb, 1);
00955                 SKIP_COUNTER(re, &s->gb, 1+11+5+1);
00956 
00957                 i+= run + 1;
00958                 if(last) i+=192;
00959           }else{
00960             int cache;
00961             cache= GET_CACHE(re, &s->gb);
00962 
00963             if(IS_3IV1)
00964                 cache ^= 0xC0000000;
00965 
00966             if (cache&0x80000000) {
00967                 if (cache&0x40000000) {
00968                     /* third escape */
00969                     SKIP_CACHE(re, &s->gb, 2);
00970                     last=  SHOW_UBITS(re, &s->gb, 1); SKIP_CACHE(re, &s->gb, 1);
00971                     run=   SHOW_UBITS(re, &s->gb, 6); LAST_SKIP_CACHE(re, &s->gb, 6);
00972                     SKIP_COUNTER(re, &s->gb, 2+1+6);
00973                     UPDATE_CACHE(re, &s->gb);
00974 
00975                     if(IS_3IV1){
00976                         level= SHOW_SBITS(re, &s->gb, 12); LAST_SKIP_BITS(re, &s->gb, 12);
00977                     }else{
00978                         if(SHOW_UBITS(re, &s->gb, 1)==0){
00979                             av_log(s->avctx, AV_LOG_ERROR, "1. marker bit missing in 3. esc\n");
00980                             return -1;
00981                         }; SKIP_CACHE(re, &s->gb, 1);
00982 
00983                         level= SHOW_SBITS(re, &s->gb, 12); SKIP_CACHE(re, &s->gb, 12);
00984 
00985                         if(SHOW_UBITS(re, &s->gb, 1)==0){
00986                             av_log(s->avctx, AV_LOG_ERROR, "2. marker bit missing in 3. esc\n");
00987                             return -1;
00988                         }; LAST_SKIP_CACHE(re, &s->gb, 1);
00989 
00990                         SKIP_COUNTER(re, &s->gb, 1+12+1);
00991                     }
00992 
00993 #if 0
00994                     if(s->error_recognition >= FF_ER_COMPLIANT){
00995                         const int abs_level= FFABS(level);
00996                         if(abs_level<=MAX_LEVEL && run<=MAX_RUN){
00997                             const int run1= run - rl->max_run[last][abs_level] - 1;
00998                             if(abs_level <= rl->max_level[last][run]){
00999                                 av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
01000                                 return -1;
01001                             }
01002                             if(s->error_recognition > FF_ER_COMPLIANT){
01003                                 if(abs_level <= rl->max_level[last][run]*2){
01004                                     av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
01005                                     return -1;
01006                                 }
01007                                 if(run1 >= 0 && abs_level <= rl->max_level[last][run1]){
01008                                     av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
01009                                     return -1;
01010                                 }
01011                             }
01012                         }
01013                     }
01014 #endif
01015                     if (level>0) level= level * qmul + qadd;
01016                     else         level= level * qmul - qadd;
01017 
01018                     if((unsigned)(level + 2048) > 4095){
01019                         if(s->error_recognition > FF_ER_COMPLIANT){
01020                             if(level > 2560 || level<-2560){
01021                                 av_log(s->avctx, AV_LOG_ERROR, "|level| overflow in 3. esc, qp=%d\n", s->qscale);
01022                                 return -1;
01023                             }
01024                         }
01025                         level= level<0 ? -2048 : 2047;
01026                     }
01027 
01028                     i+= run + 1;
01029                     if(last) i+=192;
01030                 } else {
01031                     /* second escape */
01032                     SKIP_BITS(re, &s->gb, 2);
01033                     GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
01034                     i+= run + rl->max_run[run>>7][level/qmul] +1; //FIXME opt indexing
01035                     level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01036                     LAST_SKIP_BITS(re, &s->gb, 1);
01037                 }
01038             } else {
01039                 /* first escape */
01040                 SKIP_BITS(re, &s->gb, 1);
01041                 GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
01042                 i+= run;
01043                 level = level + rl->max_level[run>>7][(run-1)&63] * qmul;//FIXME opt indexing
01044                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01045                 LAST_SKIP_BITS(re, &s->gb, 1);
01046             }
01047           }
01048         } else {
01049             i+= run;
01050             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01051             LAST_SKIP_BITS(re, &s->gb, 1);
01052         }
01053         if (i > 62){
01054             i-= 192;
01055             if(i&(~63)){
01056                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
01057                 return -1;
01058             }
01059 
01060             block[scan_table[i]] = level;
01061             break;
01062         }
01063 
01064         block[scan_table[i]] = level;
01065     }
01066     CLOSE_READER(re, &s->gb);
01067   }
01068  not_coded:
01069     if (intra) {
01070         if(!s->use_intra_dc_vlc){
01071             block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);
01072 
01073             i -= i>>31; //if(i == -1) i=0;
01074         }
01075 
01076         mpeg4_pred_ac(s, block, n, dc_pred_dir);
01077         if (s->ac_pred) {
01078             i = 63; /* XXX: not optimal */
01079         }
01080     }
01081     s->block_last_index[n] = i;
01082     return 0;
01083 }
01084 
01089 static int mpeg4_decode_partitioned_mb(MpegEncContext *s, DCTELEM block[6][64])
01090 {
01091     int cbp, mb_type;
01092     const int xy= s->mb_x + s->mb_y*s->mb_stride;
01093 
01094     mb_type= s->current_picture.mb_type[xy];
01095     cbp = s->cbp_table[xy];
01096 
01097     s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
01098 
01099     if(s->current_picture.qscale_table[xy] != s->qscale){
01100         ff_set_qscale(s, s->current_picture.qscale_table[xy] );
01101     }
01102 
01103     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
01104         int i;
01105         for(i=0; i<4; i++){
01106             s->mv[0][i][0] = s->current_picture.motion_val[0][ s->block_index[i] ][0];
01107             s->mv[0][i][1] = s->current_picture.motion_val[0][ s->block_index[i] ][1];
01108         }
01109         s->mb_intra = IS_INTRA(mb_type);
01110 
01111         if (IS_SKIP(mb_type)) {
01112             /* skip mb */
01113             for(i=0;i<6;i++)
01114                 s->block_last_index[i] = -1;
01115             s->mv_dir = MV_DIR_FORWARD;
01116             s->mv_type = MV_TYPE_16X16;
01117             if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
01118                 s->mcsel=1;
01119                 s->mb_skipped = 0;
01120             }else{
01121                 s->mcsel=0;
01122                 s->mb_skipped = 1;
01123             }
01124         }else if(s->mb_intra){
01125             s->ac_pred = IS_ACPRED(s->current_picture.mb_type[xy]);
01126         }else if(!s->mb_intra){
01127 //            s->mcsel= 0; //FIXME do we need to init that
01128 
01129             s->mv_dir = MV_DIR_FORWARD;
01130             if (IS_8X8(mb_type)) {
01131                 s->mv_type = MV_TYPE_8X8;
01132             } else {
01133                 s->mv_type = MV_TYPE_16X16;
01134             }
01135         }
01136     } else { /* I-Frame */
01137         s->mb_intra = 1;
01138         s->ac_pred = IS_ACPRED(s->current_picture.mb_type[xy]);
01139     }
01140 
01141     if (!IS_SKIP(mb_type)) {
01142         int i;
01143         s->dsp.clear_blocks(s->block[0]);
01144         /* decode each block */
01145         for (i = 0; i < 6; i++) {
01146             if(mpeg4_decode_block(s, block[i], i, cbp&32, s->mb_intra, s->rvlc) < 0){
01147                 av_log(s->avctx, AV_LOG_ERROR, "texture corrupted at %d %d %d\n", s->mb_x, s->mb_y, s->mb_intra);
01148                 return -1;
01149             }
01150             cbp+=cbp;
01151         }
01152     }
01153 
01154     /* per-MB end of slice check */
01155 
01156     if(--s->mb_num_left <= 0){
01157         if(mpeg4_is_resync(s))
01158             return SLICE_END;
01159         else
01160             return SLICE_NOEND;
01161     }else{
01162         if(mpeg4_is_resync(s)){
01163             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
01164             if(s->cbp_table[xy+delta])
01165                 return SLICE_END;
01166         }
01167         return SLICE_OK;
01168     }
01169 }
01170 
01171 static int mpeg4_decode_mb(MpegEncContext *s,
01172                       DCTELEM block[6][64])
01173 {
01174     int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
01175     int16_t *mot_val;
01176     static int8_t quant_tab[4] = { -1, -2, 1, 2 };
01177     const int xy= s->mb_x + s->mb_y * s->mb_stride;
01178 
01179     assert(s->h263_pred);
01180 
01181     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type==AV_PICTURE_TYPE_S) {
01182         do{
01183             if (get_bits1(&s->gb)) {
01184                 /* skip mb */
01185                 s->mb_intra = 0;
01186                 for(i=0;i<6;i++)
01187                     s->block_last_index[i] = -1;
01188                 s->mv_dir = MV_DIR_FORWARD;
01189                 s->mv_type = MV_TYPE_16X16;
01190                 if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE){
01191                     s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
01192                     s->mcsel=1;
01193                     s->mv[0][0][0]= get_amv(s, 0);
01194                     s->mv[0][0][1]= get_amv(s, 1);
01195 
01196                     s->mb_skipped = 0;
01197                 }else{
01198                     s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
01199                     s->mcsel=0;
01200                     s->mv[0][0][0] = 0;
01201                     s->mv[0][0][1] = 0;
01202                     s->mb_skipped = 1;
01203                 }
01204                 goto end;
01205             }
01206             cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
01207             if (cbpc < 0){
01208                 av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
01209                 return -1;
01210             }
01211         }while(cbpc == 20);
01212 
01213         s->dsp.clear_blocks(s->block[0]);
01214         dquant = cbpc & 8;
01215         s->mb_intra = ((cbpc & 4) != 0);
01216         if (s->mb_intra) goto intra;
01217 
01218         if(s->pict_type==AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE && (cbpc & 16) == 0)
01219             s->mcsel= get_bits1(&s->gb);
01220         else s->mcsel= 0;
01221         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
01222 
01223         cbp = (cbpc & 3) | (cbpy << 2);
01224         if (dquant) {
01225             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
01226         }
01227         if((!s->progressive_sequence) && (cbp || (s->workaround_bugs&FF_BUG_XVID_ILACE)))
01228             s->interlaced_dct= get_bits1(&s->gb);
01229 
01230         s->mv_dir = MV_DIR_FORWARD;
01231         if ((cbpc & 16) == 0) {
01232             if(s->mcsel){
01233                 s->current_picture.mb_type[xy]= MB_TYPE_GMC | MB_TYPE_16x16 | MB_TYPE_L0;
01234                 /* 16x16 global motion prediction */
01235                 s->mv_type = MV_TYPE_16X16;
01236                 mx= get_amv(s, 0);
01237                 my= get_amv(s, 1);
01238                 s->mv[0][0][0] = mx;
01239                 s->mv[0][0][1] = my;
01240             }else if((!s->progressive_sequence) && get_bits1(&s->gb)){
01241                 s->current_picture.mb_type[xy]= MB_TYPE_16x8 | MB_TYPE_L0 | MB_TYPE_INTERLACED;
01242                 /* 16x8 field motion prediction */
01243                 s->mv_type= MV_TYPE_FIELD;
01244 
01245                 s->field_select[0][0]= get_bits1(&s->gb);
01246                 s->field_select[0][1]= get_bits1(&s->gb);
01247 
01248                 h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
01249 
01250                 for(i=0; i<2; i++){
01251                     mx = h263_decode_motion(s, pred_x, s->f_code);
01252                     if (mx >= 0xffff)
01253                         return -1;
01254 
01255                     my = h263_decode_motion(s, pred_y/2, s->f_code);
01256                     if (my >= 0xffff)
01257                         return -1;
01258 
01259                     s->mv[0][i][0] = mx;
01260                     s->mv[0][i][1] = my;
01261                 }
01262             }else{
01263                 s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
01264                 /* 16x16 motion prediction */
01265                 s->mv_type = MV_TYPE_16X16;
01266                 h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
01267                 mx = h263_decode_motion(s, pred_x, s->f_code);
01268 
01269                 if (mx >= 0xffff)
01270                     return -1;
01271 
01272                 my = h263_decode_motion(s, pred_y, s->f_code);
01273 
01274                 if (my >= 0xffff)
01275                     return -1;
01276                 s->mv[0][0][0] = mx;
01277                 s->mv[0][0][1] = my;
01278             }
01279         } else {
01280             s->current_picture.mb_type[xy]= MB_TYPE_8x8 | MB_TYPE_L0;
01281             s->mv_type = MV_TYPE_8X8;
01282             for(i=0;i<4;i++) {
01283                 mot_val = h263_pred_motion(s, i, 0, &pred_x, &pred_y);
01284                 mx = h263_decode_motion(s, pred_x, s->f_code);
01285                 if (mx >= 0xffff)
01286                     return -1;
01287 
01288                 my = h263_decode_motion(s, pred_y, s->f_code);
01289                 if (my >= 0xffff)
01290                     return -1;
01291                 s->mv[0][i][0] = mx;
01292                 s->mv[0][i][1] = my;
01293                 mot_val[0] = mx;
01294                 mot_val[1] = my;
01295             }
01296         }
01297     } else if(s->pict_type==AV_PICTURE_TYPE_B) {
01298         int modb1; // first bit of modb
01299         int modb2; // second bit of modb
01300         int mb_type;
01301 
01302         s->mb_intra = 0; //B-frames never contain intra blocks
01303         s->mcsel=0;      //     ...               true gmc blocks
01304 
01305         if(s->mb_x==0){
01306             for(i=0; i<2; i++){
01307                 s->last_mv[i][0][0]=
01308                 s->last_mv[i][0][1]=
01309                 s->last_mv[i][1][0]=
01310                 s->last_mv[i][1][1]= 0;
01311             }
01312 
01313             ff_thread_await_progress((AVFrame*)s->next_picture_ptr, s->mb_y, 0);
01314         }
01315 
01316         /* if we skipped it in the future P Frame than skip it now too */
01317         s->mb_skipped= s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x]; // Note, skiptab=0 if last was GMC
01318 
01319         if(s->mb_skipped){
01320                 /* skip mb */
01321             for(i=0;i<6;i++)
01322                 s->block_last_index[i] = -1;
01323 
01324             s->mv_dir = MV_DIR_FORWARD;
01325             s->mv_type = MV_TYPE_16X16;
01326             s->mv[0][0][0] = 0;
01327             s->mv[0][0][1] = 0;
01328             s->mv[1][0][0] = 0;
01329             s->mv[1][0][1] = 0;
01330             s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
01331             goto end;
01332         }
01333 
01334         modb1= get_bits1(&s->gb);
01335         if(modb1){
01336             mb_type= MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1; //like MB_TYPE_B_DIRECT but no vectors coded
01337             cbp=0;
01338         }else{
01339             modb2= get_bits1(&s->gb);
01340             mb_type= get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
01341             if(mb_type<0){
01342                 av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
01343                 return -1;
01344             }
01345             mb_type= mb_type_b_map[ mb_type ];
01346             if(modb2) cbp= 0;
01347             else{
01348                 s->dsp.clear_blocks(s->block[0]);
01349                 cbp= get_bits(&s->gb, 6);
01350             }
01351 
01352             if ((!IS_DIRECT(mb_type)) && cbp) {
01353                 if(get_bits1(&s->gb)){
01354                     ff_set_qscale(s, s->qscale + get_bits1(&s->gb)*4 - 2);
01355                 }
01356             }
01357 
01358             if(!s->progressive_sequence){
01359                 if(cbp)
01360                     s->interlaced_dct= get_bits1(&s->gb);
01361 
01362                 if(!IS_DIRECT(mb_type) && get_bits1(&s->gb)){
01363                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
01364                     mb_type &= ~MB_TYPE_16x16;
01365 
01366                     if(USES_LIST(mb_type, 0)){
01367                         s->field_select[0][0]= get_bits1(&s->gb);
01368                         s->field_select[0][1]= get_bits1(&s->gb);
01369                     }
01370                     if(USES_LIST(mb_type, 1)){
01371                         s->field_select[1][0]= get_bits1(&s->gb);
01372                         s->field_select[1][1]= get_bits1(&s->gb);
01373                     }
01374                 }
01375             }
01376 
01377             s->mv_dir = 0;
01378             if((mb_type & (MB_TYPE_DIRECT2|MB_TYPE_INTERLACED)) == 0){
01379                 s->mv_type= MV_TYPE_16X16;
01380 
01381                 if(USES_LIST(mb_type, 0)){
01382                     s->mv_dir = MV_DIR_FORWARD;
01383 
01384                     mx = h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
01385                     my = h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
01386                     s->last_mv[0][1][0]= s->last_mv[0][0][0]= s->mv[0][0][0] = mx;
01387                     s->last_mv[0][1][1]= s->last_mv[0][0][1]= s->mv[0][0][1] = my;
01388                 }
01389 
01390                 if(USES_LIST(mb_type, 1)){
01391                     s->mv_dir |= MV_DIR_BACKWARD;
01392 
01393                     mx = h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
01394                     my = h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
01395                     s->last_mv[1][1][0]= s->last_mv[1][0][0]= s->mv[1][0][0] = mx;
01396                     s->last_mv[1][1][1]= s->last_mv[1][0][1]= s->mv[1][0][1] = my;
01397                 }
01398             }else if(!IS_DIRECT(mb_type)){
01399                 s->mv_type= MV_TYPE_FIELD;
01400 
01401                 if(USES_LIST(mb_type, 0)){
01402                     s->mv_dir = MV_DIR_FORWARD;
01403 
01404                     for(i=0; i<2; i++){
01405                         mx = h263_decode_motion(s, s->last_mv[0][i][0]  , s->f_code);
01406                         my = h263_decode_motion(s, s->last_mv[0][i][1]/2, s->f_code);
01407                         s->last_mv[0][i][0]=  s->mv[0][i][0] = mx;
01408                         s->last_mv[0][i][1]= (s->mv[0][i][1] = my)*2;
01409                     }
01410                 }
01411 
01412                 if(USES_LIST(mb_type, 1)){
01413                     s->mv_dir |= MV_DIR_BACKWARD;
01414 
01415                     for(i=0; i<2; i++){
01416                         mx = h263_decode_motion(s, s->last_mv[1][i][0]  , s->b_code);
01417                         my = h263_decode_motion(s, s->last_mv[1][i][1]/2, s->b_code);
01418                         s->last_mv[1][i][0]=  s->mv[1][i][0] = mx;
01419                         s->last_mv[1][i][1]= (s->mv[1][i][1] = my)*2;
01420                     }
01421                 }
01422             }
01423         }
01424 
01425         if(IS_DIRECT(mb_type)){
01426             if(IS_SKIP(mb_type))
01427                 mx=my=0;
01428             else{
01429                 mx = h263_decode_motion(s, 0, 1);
01430                 my = h263_decode_motion(s, 0, 1);
01431             }
01432 
01433             s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
01434             mb_type |= ff_mpeg4_set_direct_mv(s, mx, my);
01435         }
01436         s->current_picture.mb_type[xy]= mb_type;
01437     } else { /* I-Frame */
01438         do{
01439             cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
01440             if (cbpc < 0){
01441                 av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
01442                 return -1;
01443             }
01444         }while(cbpc == 8);
01445 
01446         dquant = cbpc & 4;
01447         s->mb_intra = 1;
01448 intra:
01449         s->ac_pred = get_bits1(&s->gb);
01450         if(s->ac_pred)
01451             s->current_picture.mb_type[xy]= MB_TYPE_INTRA | MB_TYPE_ACPRED;
01452         else
01453             s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
01454 
01455         cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
01456         if(cbpy<0){
01457             av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
01458             return -1;
01459         }
01460         cbp = (cbpc & 3) | (cbpy << 2);
01461 
01462         s->use_intra_dc_vlc= s->qscale < s->intra_dc_threshold;
01463 
01464         if (dquant) {
01465             ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
01466         }
01467 
01468         if(!s->progressive_sequence)
01469             s->interlaced_dct= get_bits1(&s->gb);
01470 
01471         s->dsp.clear_blocks(s->block[0]);
01472         /* decode each block */
01473         for (i = 0; i < 6; i++) {
01474             if (mpeg4_decode_block(s, block[i], i, cbp&32, 1, 0) < 0)
01475                 return -1;
01476             cbp+=cbp;
01477         }
01478         goto end;
01479     }
01480 
01481     /* decode each block */
01482     for (i = 0; i < 6; i++) {
01483         if (mpeg4_decode_block(s, block[i], i, cbp&32, 0, 0) < 0)
01484             return -1;
01485         cbp+=cbp;
01486     }
01487 end:
01488 
01489         /* per-MB end of slice check */
01490     if(s->codec_id==CODEC_ID_MPEG4){
01491         if(mpeg4_is_resync(s)){
01492             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
01493 
01494             if(s->pict_type==AV_PICTURE_TYPE_B){
01495                 ff_thread_await_progress((AVFrame*)s->next_picture_ptr,
01496                                         (s->mb_x + delta >= s->mb_width) ? FFMIN(s->mb_y+1, s->mb_height-1) : s->mb_y, 0);
01497             }
01498 
01499             if(s->pict_type==AV_PICTURE_TYPE_B && s->next_picture.mbskip_table[xy + delta])
01500                 return SLICE_OK;
01501             return SLICE_END;
01502         }
01503     }
01504 
01505     return SLICE_OK;
01506 }
01507 
01508 
01509 static int mpeg4_decode_gop_header(MpegEncContext * s, GetBitContext *gb){
01510     int hours, minutes, seconds;
01511 
01512     if(!show_bits(gb, 23)){
01513         av_log(s->avctx, AV_LOG_WARNING, "GOP header invalid\n");
01514         return -1;
01515     }
01516 
01517     hours= get_bits(gb, 5);
01518     minutes= get_bits(gb, 6);
01519     skip_bits1(gb);
01520     seconds= get_bits(gb, 6);
01521 
01522     s->time_base= seconds + 60*(minutes + 60*hours);
01523 
01524     skip_bits1(gb);
01525     skip_bits1(gb);
01526 
01527     return 0;
01528 }
01529 
01530 static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
01531     int width, height, vo_ver_id;
01532 
01533     /* vol header */
01534     skip_bits(gb, 1); /* random access */
01535     s->vo_type= get_bits(gb, 8);
01536     if (get_bits1(gb) != 0) { /* is_ol_id */
01537         vo_ver_id = get_bits(gb, 4); /* vo_ver_id */
01538         skip_bits(gb, 3); /* vo_priority */
01539     } else {
01540         vo_ver_id = 1;
01541     }
01542     s->aspect_ratio_info= get_bits(gb, 4);
01543     if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){
01544         s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
01545         s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
01546     }else{
01547         s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
01548     }
01549 
01550     if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
01551         int chroma_format= get_bits(gb, 2);
01552         if(chroma_format!=CHROMA_420){
01553             av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
01554         }
01555         s->low_delay= get_bits1(gb);
01556         if(get_bits1(gb)){ /* vbv parameters */
01557             get_bits(gb, 15);   /* first_half_bitrate */
01558             skip_bits1(gb);     /* marker */
01559             get_bits(gb, 15);   /* latter_half_bitrate */
01560             skip_bits1(gb);     /* marker */
01561             get_bits(gb, 15);   /* first_half_vbv_buffer_size */
01562             skip_bits1(gb);     /* marker */
01563             get_bits(gb, 3);    /* latter_half_vbv_buffer_size */
01564             get_bits(gb, 11);   /* first_half_vbv_occupancy */
01565             skip_bits1(gb);     /* marker */
01566             get_bits(gb, 15);   /* latter_half_vbv_occupancy */
01567             skip_bits1(gb);     /* marker */
01568         }
01569     }else{
01570         // set low delay flag only once the smartest? low delay detection won't be overriden
01571         if(s->picture_number==0)
01572             s->low_delay=0;
01573     }
01574 
01575     s->shape = get_bits(gb, 2); /* vol shape */
01576     if(s->shape != RECT_SHAPE) av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
01577     if(s->shape == GRAY_SHAPE && vo_ver_id != 1){
01578         av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
01579         skip_bits(gb, 4);  //video_object_layer_shape_extension
01580     }
01581 
01582     check_marker(gb, "before time_increment_resolution");
01583 
01584     s->avctx->time_base.den = get_bits(gb, 16);
01585     if(!s->avctx->time_base.den){
01586         av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
01587         s->avctx->time_base.num = 0;
01588         return -1;
01589     }
01590 
01591     s->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
01592     if (s->time_increment_bits < 1)
01593         s->time_increment_bits = 1;
01594 
01595     check_marker(gb, "before fixed_vop_rate");
01596 
01597     if (get_bits1(gb) != 0) {   /* fixed_vop_rate  */
01598         s->avctx->time_base.num = get_bits(gb, s->time_increment_bits);
01599     }else
01600         s->avctx->time_base.num = 1;
01601 
01602     s->t_frame=0;
01603 
01604     if (s->shape != BIN_ONLY_SHAPE) {
01605         if (s->shape == RECT_SHAPE) {
01606             skip_bits1(gb);   /* marker */
01607             width = get_bits(gb, 13);
01608             skip_bits1(gb);   /* marker */
01609             height = get_bits(gb, 13);
01610             skip_bits1(gb);   /* marker */
01611             if(width && height && !(s->width && s->codec_tag == AV_RL32("MP4S"))){ /* they should be non zero but who knows ... */
01612                 s->width = width;
01613                 s->height = height;
01614             }
01615         }
01616 
01617         s->progressive_sequence=
01618         s->progressive_frame= get_bits1(gb)^1;
01619         s->interlaced_dct=0;
01620         if(!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
01621             av_log(s->avctx, AV_LOG_INFO, "MPEG4 OBMC not supported (very likely buggy encoder)\n");   /* OBMC Disable */
01622         if (vo_ver_id == 1) {
01623             s->vol_sprite_usage = get_bits1(gb); /* vol_sprite_usage */
01624         } else {
01625             s->vol_sprite_usage = get_bits(gb, 2); /* vol_sprite_usage */
01626         }
01627         if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
01628         if(s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE){
01629             if(s->vol_sprite_usage==STATIC_SPRITE){
01630                 s->sprite_width = get_bits(gb, 13);
01631                 skip_bits1(gb); /* marker */
01632                 s->sprite_height= get_bits(gb, 13);
01633                 skip_bits1(gb); /* marker */
01634                 s->sprite_left  = get_bits(gb, 13);
01635                 skip_bits1(gb); /* marker */
01636                 s->sprite_top   = get_bits(gb, 13);
01637                 skip_bits1(gb); /* marker */
01638             }
01639             s->num_sprite_warping_points= get_bits(gb, 6);
01640             if(s->num_sprite_warping_points > 3){
01641                 av_log(s->avctx, AV_LOG_ERROR, "%d sprite_warping_points\n", s->num_sprite_warping_points);
01642                 s->num_sprite_warping_points= 0;
01643                 return -1;
01644             }
01645             s->sprite_warping_accuracy = get_bits(gb, 2);
01646             s->sprite_brightness_change= get_bits1(gb);
01647             if(s->vol_sprite_usage==STATIC_SPRITE)
01648                 s->low_latency_sprite= get_bits1(gb);
01649         }
01650         // FIXME sadct disable bit if verid!=1 && shape not rect
01651 
01652         if (get_bits1(gb) == 1) {   /* not_8_bit */
01653             s->quant_precision = get_bits(gb, 4); /* quant_precision */
01654             if(get_bits(gb, 4)!=8) av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n"); /* bits_per_pixel */
01655             if(s->quant_precision!=5) av_log(s->avctx, AV_LOG_ERROR, "quant precision %d\n", s->quant_precision);
01656         } else {
01657             s->quant_precision = 5;
01658         }
01659 
01660         // FIXME a bunch of grayscale shape things
01661 
01662         if((s->mpeg_quant=get_bits1(gb))){ /* vol_quant_type */
01663             int i, v;
01664 
01665             /* load default matrixes */
01666             for(i=0; i<64; i++){
01667                 int j= s->dsp.idct_permutation[i];
01668                 v= ff_mpeg4_default_intra_matrix[i];
01669                 s->intra_matrix[j]= v;
01670                 s->chroma_intra_matrix[j]= v;
01671 
01672                 v= ff_mpeg4_default_non_intra_matrix[i];
01673                 s->inter_matrix[j]= v;
01674                 s->chroma_inter_matrix[j]= v;
01675             }
01676 
01677             /* load custom intra matrix */
01678             if(get_bits1(gb)){
01679                 int last=0;
01680                 for(i=0; i<64; i++){
01681                     int j;
01682                     v= get_bits(gb, 8);
01683                     if(v==0) break;
01684 
01685                     last= v;
01686                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01687                     s->intra_matrix[j]= v;
01688                     s->chroma_intra_matrix[j]= v;
01689                 }
01690 
01691                 /* replicate last value */
01692                 for(; i<64; i++){
01693                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01694                     s->intra_matrix[j]= last;
01695                     s->chroma_intra_matrix[j]= last;
01696                 }
01697             }
01698 
01699             /* load custom non intra matrix */
01700             if(get_bits1(gb)){
01701                 int last=0;
01702                 for(i=0; i<64; i++){
01703                     int j;
01704                     v= get_bits(gb, 8);
01705                     if(v==0) break;
01706 
01707                     last= v;
01708                     j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01709                     s->inter_matrix[j]= v;
01710                     s->chroma_inter_matrix[j]= v;
01711                 }
01712 
01713                 /* replicate last value */
01714                 for(; i<64; i++){
01715                     int j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01716                     s->inter_matrix[j]= last;
01717                     s->chroma_inter_matrix[j]= last;
01718                 }
01719             }
01720 
01721             // FIXME a bunch of grayscale shape things
01722         }
01723 
01724         if(vo_ver_id != 1)
01725              s->quarter_sample= get_bits1(gb);
01726         else s->quarter_sample=0;
01727 
01728         if(!get_bits1(gb)){
01729             int pos= get_bits_count(gb);
01730             int estimation_method= get_bits(gb, 2);
01731             if(estimation_method<2){
01732                 if(!get_bits1(gb)){
01733                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //opaque
01734                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //transparent
01735                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_cae
01736                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //inter_cae
01737                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //no_update
01738                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //upampling
01739                 }
01740                 if(!get_bits1(gb)){
01741                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //intra_blocks
01742                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter_blocks
01743                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //inter4v_blocks
01744                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //not coded blocks
01745                 }
01746                 if(!check_marker(gb, "in complexity estimation part 1")){
01747                     skip_bits_long(gb, pos - get_bits_count(gb));
01748                     goto no_cplx_est;
01749                 }
01750                 if(!get_bits1(gb)){
01751                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_coeffs
01752                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //dct_lines
01753                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //vlc_syms
01754                     s->cplx_estimation_trash_i += 4*get_bits1(gb); //vlc_bits
01755                 }
01756                 if(!get_bits1(gb)){
01757                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //apm
01758                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //npm
01759                     s->cplx_estimation_trash_b += 8*get_bits1(gb); //interpolate_mc_q
01760                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //forwback_mc_q
01761                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel2
01762                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //halfpel4
01763                 }
01764                 if(!check_marker(gb, "in complexity estimation part 2")){
01765                     skip_bits_long(gb, pos - get_bits_count(gb));
01766                     goto no_cplx_est;
01767                 }
01768                 if(estimation_method==1){
01769                     s->cplx_estimation_trash_i += 8*get_bits1(gb); //sadct
01770                     s->cplx_estimation_trash_p += 8*get_bits1(gb); //qpel
01771                 }
01772             }else
01773                 av_log(s->avctx, AV_LOG_ERROR, "Invalid Complexity estimation method %d\n", estimation_method);
01774         }else{
01775 no_cplx_est:
01776             s->cplx_estimation_trash_i=
01777             s->cplx_estimation_trash_p=
01778             s->cplx_estimation_trash_b= 0;
01779         }
01780 
01781         s->resync_marker= !get_bits1(gb); /* resync_marker_disabled */
01782 
01783         s->data_partitioning= get_bits1(gb);
01784         if(s->data_partitioning){
01785             s->rvlc= get_bits1(gb);
01786         }
01787 
01788         if(vo_ver_id != 1) {
01789             s->new_pred= get_bits1(gb);
01790             if(s->new_pred){
01791                 av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
01792                 skip_bits(gb, 2); /* requested upstream message type */
01793                 skip_bits1(gb); /* newpred segment type */
01794             }
01795             s->reduced_res_vop= get_bits1(gb);
01796             if(s->reduced_res_vop) av_log(s->avctx, AV_LOG_ERROR, "reduced resolution VOP not supported\n");
01797         }
01798         else{
01799             s->new_pred=0;
01800             s->reduced_res_vop= 0;
01801         }
01802 
01803         s->scalability= get_bits1(gb);
01804 
01805         if (s->scalability) {
01806             GetBitContext bak= *gb;
01807             int h_sampling_factor_n;
01808             int h_sampling_factor_m;
01809             int v_sampling_factor_n;
01810             int v_sampling_factor_m;
01811 
01812             s->hierachy_type= get_bits1(gb);
01813             skip_bits(gb, 4);  /* ref_layer_id */
01814             skip_bits1(gb);    /* ref_layer_sampling_dir */
01815             h_sampling_factor_n= get_bits(gb, 5);
01816             h_sampling_factor_m= get_bits(gb, 5);
01817             v_sampling_factor_n= get_bits(gb, 5);
01818             v_sampling_factor_m= get_bits(gb, 5);
01819             s->enhancement_type= get_bits1(gb);
01820 
01821             if(   h_sampling_factor_n==0 || h_sampling_factor_m==0
01822                || v_sampling_factor_n==0 || v_sampling_factor_m==0){
01823                 /* illegal scalability header (VERY broken encoder),
01824                  * trying to workaround */
01825                 s->scalability=0;
01826                 *gb= bak;
01827             }else
01828                 av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");
01829 
01830             // bin shape stuff FIXME
01831         }
01832     }
01833     return 0;
01834 }
01835 
01840 static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
01841     char buf[256];
01842     int i;
01843     int e;
01844     int ver = 0, build = 0, ver2 = 0, ver3 = 0;
01845     char last;
01846 
01847     for(i=0; i<255 && get_bits_count(gb) < gb->size_in_bits; i++){
01848         if(show_bits(gb, 23) == 0) break;
01849         buf[i]= get_bits(gb, 8);
01850     }
01851     buf[i]=0;
01852 
01853     /* divx detection */
01854     e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
01855     if(e<2)
01856         e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
01857     if(e>=2){
01858         s->divx_version= ver;
01859         s->divx_build= build;
01860         s->divx_packed= e==3 && last=='p';
01861         if(s->divx_packed && !s->showed_packed_warning) {
01862             av_log(s->avctx, AV_LOG_WARNING, "Invalid and inefficient vfw-avi packed B frames detected\n");
01863             s->showed_packed_warning=1;
01864         }
01865     }
01866 
01867     /* ffmpeg detection */
01868     e=sscanf(buf, "FFmpe%*[^b]b%d", &build)+3;
01869     if(e!=4)
01870         e=sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
01871     if(e!=4){
01872         e=sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3)+1;
01873         if (e>1)
01874             build= (ver<<16) + (ver2<<8) + ver3;
01875     }
01876     if(e!=4){
01877         if(strcmp(buf, "ffmpeg")==0){
01878             s->lavc_build= 4600;
01879         }
01880     }
01881     if(e==4){
01882         s->lavc_build= build;
01883     }
01884 
01885     /* Xvid detection */
01886     e=sscanf(buf, "XviD%d", &build);
01887     if(e==1){
01888         s->xvid_build= build;
01889     }
01890 
01891     return 0;
01892 }
01893 
01894 static int decode_vop_header(MpegEncContext *s, GetBitContext *gb){
01895     int time_incr, time_increment;
01896 
01897     s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I;        /* pict type: I = 0 , P = 1 */
01898     if(s->pict_type==AV_PICTURE_TYPE_B && s->low_delay && s->vol_control_parameters==0 && !(s->flags & CODEC_FLAG_LOW_DELAY)){
01899         av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
01900         s->low_delay=0;
01901     }
01902 
01903     s->partitioned_frame= s->data_partitioning && s->pict_type!=AV_PICTURE_TYPE_B;
01904     if(s->partitioned_frame)
01905         s->decode_mb= mpeg4_decode_partitioned_mb;
01906     else
01907         s->decode_mb= mpeg4_decode_mb;
01908 
01909     time_incr=0;
01910     while (get_bits1(gb) != 0)
01911         time_incr++;
01912 
01913     check_marker(gb, "before time_increment");
01914 
01915     if(s->time_increment_bits==0 || !(show_bits(gb, s->time_increment_bits+1)&1)){
01916         av_log(s->avctx, AV_LOG_ERROR, "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");
01917 
01918         for(s->time_increment_bits=1 ;s->time_increment_bits<16; s->time_increment_bits++){
01919             if (    s->pict_type == AV_PICTURE_TYPE_P
01920                 || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE)) {
01921                 if((show_bits(gb, s->time_increment_bits+6)&0x37) == 0x30) break;
01922             }else
01923                 if((show_bits(gb, s->time_increment_bits+5)&0x1F) == 0x18) break;
01924         }
01925 
01926         av_log(s->avctx, AV_LOG_ERROR, "my guess is %d bits ;)\n",s->time_increment_bits);
01927     }
01928 
01929     if(IS_3IV1) time_increment= get_bits1(gb); //FIXME investigate further
01930     else time_increment= get_bits(gb, s->time_increment_bits);
01931 
01932     if(s->pict_type!=AV_PICTURE_TYPE_B){
01933         s->last_time_base= s->time_base;
01934         s->time_base+= time_incr;
01935         s->time= s->time_base*s->avctx->time_base.den + time_increment;
01936         if(s->workaround_bugs&FF_BUG_UMP4){
01937             if(s->time < s->last_non_b_time){
01938                 /* header is not mpeg-4-compatible, broken encoder,
01939                  * trying to workaround */
01940                 s->time_base++;
01941                 s->time+= s->avctx->time_base.den;
01942             }
01943         }
01944         s->pp_time= s->time - s->last_non_b_time;
01945         s->last_non_b_time= s->time;
01946     }else{
01947         s->time= (s->last_time_base + time_incr)*s->avctx->time_base.den + time_increment;
01948         s->pb_time= s->pp_time - (s->last_non_b_time - s->time);
01949         if(s->pp_time <=s->pb_time || s->pp_time <= s->pp_time - s->pb_time || s->pp_time<=0){
01950             /* messed up order, maybe after seeking? skipping current b-frame */
01951             return FRAME_SKIPPED;
01952         }
01953         ff_mpeg4_init_direct_mv(s);
01954 
01955         if(s->t_frame==0) s->t_frame= s->pb_time;
01956         if(s->t_frame==0) s->t_frame=1; // 1/0 protection
01957         s->pp_field_time= (  ROUNDED_DIV(s->last_non_b_time, s->t_frame)
01958                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
01959         s->pb_field_time= (  ROUNDED_DIV(s->time, s->t_frame)
01960                            - ROUNDED_DIV(s->last_non_b_time - s->pp_time, s->t_frame))*2;
01961         if(!s->progressive_sequence){
01962             if(s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1)
01963                 return FRAME_SKIPPED;
01964         }
01965     }
01966 
01967     if(s->avctx->time_base.num)
01968         s->current_picture_ptr->pts= (s->time + s->avctx->time_base.num/2) / s->avctx->time_base.num;
01969     else
01970         s->current_picture_ptr->pts= AV_NOPTS_VALUE;
01971     if(s->avctx->debug&FF_DEBUG_PTS)
01972         av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n", s->current_picture_ptr->pts);
01973 
01974     check_marker(gb, "before vop_coded");
01975 
01976     /* vop coded */
01977     if (get_bits1(gb) != 1){
01978         if(s->avctx->debug&FF_DEBUG_PICT_INFO)
01979             av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
01980         return FRAME_SKIPPED;
01981     }
01982     if (s->shape != BIN_ONLY_SHAPE && ( s->pict_type == AV_PICTURE_TYPE_P
01983                           || (s->pict_type == AV_PICTURE_TYPE_S && s->vol_sprite_usage==GMC_SPRITE))) {
01984         /* rounding type for motion estimation */
01985         s->no_rounding = get_bits1(gb);
01986     } else {
01987         s->no_rounding = 0;
01988     }
01989 //FIXME reduced res stuff
01990 
01991      if (s->shape != RECT_SHAPE) {
01992          if (s->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
01993              skip_bits(gb, 13); /* width */
01994              skip_bits1(gb);   /* marker */
01995              skip_bits(gb, 13); /* height */
01996              skip_bits1(gb);   /* marker */
01997              skip_bits(gb, 13); /* hor_spat_ref */
01998              skip_bits1(gb);   /* marker */
01999              skip_bits(gb, 13); /* ver_spat_ref */
02000          }
02001          skip_bits1(gb); /* change_CR_disable */
02002 
02003          if (get_bits1(gb) != 0) {
02004              skip_bits(gb, 8); /* constant_alpha_value */
02005          }
02006      }
02007 //FIXME complexity estimation stuff
02008 
02009      if (s->shape != BIN_ONLY_SHAPE) {
02010          skip_bits_long(gb, s->cplx_estimation_trash_i);
02011          if(s->pict_type != AV_PICTURE_TYPE_I)
02012             skip_bits_long(gb, s->cplx_estimation_trash_p);
02013          if(s->pict_type == AV_PICTURE_TYPE_B)
02014             skip_bits_long(gb, s->cplx_estimation_trash_b);
02015 
02016          s->intra_dc_threshold= mpeg4_dc_threshold[ get_bits(gb, 3) ];
02017          if(!s->progressive_sequence){
02018              s->top_field_first= get_bits1(gb);
02019              s->alternate_scan= get_bits1(gb);
02020          }else
02021              s->alternate_scan= 0;
02022      }
02023 
02024      if(s->alternate_scan){
02025          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
02026          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
02027          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
02028          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
02029      } else{
02030          ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
02031          ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
02032          ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
02033          ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
02034      }
02035 
02036      if(s->pict_type == AV_PICTURE_TYPE_S && (s->vol_sprite_usage==STATIC_SPRITE || s->vol_sprite_usage==GMC_SPRITE)){
02037          mpeg4_decode_sprite_trajectory(s, gb);
02038          if(s->sprite_brightness_change) av_log(s->avctx, AV_LOG_ERROR, "sprite_brightness_change not supported\n");
02039          if(s->vol_sprite_usage==STATIC_SPRITE) av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
02040      }
02041 
02042      if (s->shape != BIN_ONLY_SHAPE) {
02043          s->chroma_qscale= s->qscale = get_bits(gb, s->quant_precision);
02044          if(s->qscale==0){
02045              av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (qscale=0)\n");
02046              return -1; // makes no sense to continue, as there is nothing left from the image then
02047          }
02048 
02049          if (s->pict_type != AV_PICTURE_TYPE_I) {
02050              s->f_code = get_bits(gb, 3);       /* fcode_for */
02051              if(s->f_code==0){
02052                  av_log(s->avctx, AV_LOG_ERROR, "Error, header damaged or not MPEG4 header (f_code=0)\n");
02053                  return -1; // makes no sense to continue, as the MV decoding will break very quickly
02054              }
02055          }else
02056              s->f_code=1;
02057 
02058          if (s->pict_type == AV_PICTURE_TYPE_B) {
02059              s->b_code = get_bits(gb, 3);
02060          }else
02061              s->b_code=1;
02062 
02063          if(s->avctx->debug&FF_DEBUG_PICT_INFO){
02064              av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d\n",
02065                  s->qscale, s->f_code, s->b_code,
02066                  s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
02067                  gb->size_in_bits,s->progressive_sequence, s->alternate_scan, s->top_field_first,
02068                  s->quarter_sample ? "q" : "h", s->data_partitioning, s->resync_marker, s->num_sprite_warping_points,
02069                  s->sprite_warping_accuracy, 1-s->no_rounding, s->vo_type, s->vol_control_parameters ? " VOLC" : " ", s->intra_dc_threshold, s->cplx_estimation_trash_i, s->cplx_estimation_trash_p, s->cplx_estimation_trash_b);
02070          }
02071 
02072          if(!s->scalability){
02073              if (s->shape!=RECT_SHAPE && s->pict_type!=AV_PICTURE_TYPE_I) {
02074                  skip_bits1(gb); // vop shape coding type
02075              }
02076          }else{
02077              if(s->enhancement_type){
02078                  int load_backward_shape= get_bits1(gb);
02079                  if(load_backward_shape){
02080                      av_log(s->avctx, AV_LOG_ERROR, "load backward shape isn't supported\n");
02081                  }
02082              }
02083              skip_bits(gb, 2); //ref_select_code
02084          }
02085      }
02086      /* detect buggy encoders which don't set the low_delay flag (divx4/xvid/opendivx)*/
02087      // note we cannot detect divx5 without b-frames easily (although it's buggy too)
02088      if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==-1 && s->picture_number==0){
02089          av_log(s->avctx, AV_LOG_WARNING, "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
02090          s->low_delay=1;
02091      }
02092 
02093      s->picture_number++; // better than pic number==0 always ;)
02094 
02095      s->y_dc_scale_table= ff_mpeg4_y_dc_scale_table; //FIXME add short header support
02096      s->c_dc_scale_table= ff_mpeg4_c_dc_scale_table;
02097 
02098      if(s->workaround_bugs&FF_BUG_EDGE){
02099          s->h_edge_pos= s->width;
02100          s->v_edge_pos= s->height;
02101      }
02102      return 0;
02103 }
02104 
02111 int ff_mpeg4_decode_picture_header(MpegEncContext * s, GetBitContext *gb)
02112 {
02113     int startcode, v;
02114 
02115     /* search next start code */
02116     align_get_bits(gb);
02117 
02118     if(s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630){
02119         skip_bits(gb, 24);
02120         if(get_bits(gb, 8) == 0xF0)
02121             goto end;
02122     }
02123 
02124     startcode = 0xff;
02125     for(;;) {
02126         if(get_bits_count(gb) >= gb->size_in_bits){
02127             if(gb->size_in_bits==8 && (s->divx_version>=0 || s->xvid_build>=0)){
02128                 av_log(s->avctx, AV_LOG_WARNING, "frame skip %d\n", gb->size_in_bits);
02129                 return FRAME_SKIPPED; //divx bug
02130             }else
02131                 return -1; //end of stream
02132         }
02133 
02134         /* use the bits after the test */
02135         v = get_bits(gb, 8);
02136         startcode = ((startcode << 8) | v) & 0xffffffff;
02137 
02138         if((startcode&0xFFFFFF00) != 0x100)
02139             continue; //no startcode
02140 
02141         if(s->avctx->debug&FF_DEBUG_STARTCODE){
02142             av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
02143             if     (startcode<=0x11F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
02144             else if(startcode<=0x12F) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
02145             else if(startcode<=0x13F) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
02146             else if(startcode<=0x15F) av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
02147             else if(startcode<=0x1AF) av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
02148             else if(startcode==0x1B0) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
02149             else if(startcode==0x1B1) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
02150             else if(startcode==0x1B2) av_log(s->avctx, AV_LOG_DEBUG, "User Data");
02151             else if(startcode==0x1B3) av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
02152             else if(startcode==0x1B4) av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
02153             else if(startcode==0x1B5) av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
02154             else if(startcode==0x1B6) av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
02155             else if(startcode==0x1B7) av_log(s->avctx, AV_LOG_DEBUG, "slice start");
02156             else if(startcode==0x1B8) av_log(s->avctx, AV_LOG_DEBUG, "extension start");
02157             else if(startcode==0x1B9) av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
02158             else if(startcode==0x1BA) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
02159             else if(startcode==0x1BB) av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
02160             else if(startcode==0x1BC) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
02161             else if(startcode==0x1BD) av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
02162             else if(startcode==0x1BE) av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
02163             else if(startcode==0x1BF) av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
02164             else if(startcode==0x1C0) av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
02165             else if(startcode==0x1C1) av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
02166             else if(startcode==0x1C2) av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
02167             else if(startcode==0x1C3) av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
02168             else if(startcode<=0x1C5) av_log(s->avctx, AV_LOG_DEBUG, "reserved");
02169             else if(startcode<=0x1FF) av_log(s->avctx, AV_LOG_DEBUG, "System start");
02170             av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
02171         }
02172 
02173         if(startcode >= 0x120 && startcode <= 0x12F){
02174             if(decode_vol_header(s, gb) < 0)
02175                 return -1;
02176         }
02177         else if(startcode == USER_DATA_STARTCODE){
02178             decode_user_data(s, gb);
02179         }
02180         else if(startcode == GOP_STARTCODE){
02181             mpeg4_decode_gop_header(s, gb);
02182         }
02183         else if(startcode == VOP_STARTCODE){
02184             break;
02185         }
02186 
02187         align_get_bits(gb);
02188         startcode = 0xff;
02189     }
02190 end:
02191     if(s->flags& CODEC_FLAG_LOW_DELAY)
02192         s->low_delay=1;
02193     s->avctx->has_b_frames= !s->low_delay;
02194     return decode_vop_header(s, gb);
02195 }
02196 
02197 static av_cold int decode_init(AVCodecContext *avctx)
02198 {
02199     MpegEncContext *s = avctx->priv_data;
02200     int ret;
02201     static int done = 0;
02202 
02203     s->divx_version=
02204     s->divx_build=
02205     s->xvid_build=
02206     s->lavc_build= -1;
02207 
02208     if((ret=ff_h263_decode_init(avctx)) < 0)
02209         return ret;
02210 
02211     if (!done) {
02212         done = 1;
02213 
02214         init_rl(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);
02215         init_rl(&rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
02216         init_rl(&rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
02217         INIT_VLC_RL(ff_mpeg4_rl_intra, 554);
02218         INIT_VLC_RL(rvlc_rl_inter, 1072);
02219         INIT_VLC_RL(rvlc_rl_intra, 1072);
02220         INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
02221                  &ff_mpeg4_DCtab_lum[0][1], 2, 1,
02222                  &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
02223         INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
02224                  &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
02225                  &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
02226         INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
02227                  &sprite_trajectory_tab[0][1], 4, 2,
02228                  &sprite_trajectory_tab[0][0], 4, 2, 128);
02229         INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
02230                  &mb_type_b_tab[0][1], 2, 1,
02231                  &mb_type_b_tab[0][0], 2, 1, 16);
02232     }
02233 
02234     s->h263_pred = 1;
02235     s->low_delay = 0; //default, might be overriden in the vol header during header parsing
02236     s->decode_mb= mpeg4_decode_mb;
02237     s->time_increment_bits = 4; /* default value for broken headers */
02238     avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
02239 
02240     return 0;
02241 }
02242 
02243 AVCodec ff_mpeg4_decoder = {
02244     "mpeg4",
02245     AVMEDIA_TYPE_VIDEO,
02246     CODEC_ID_MPEG4,
02247     sizeof(MpegEncContext),
02248     decode_init,
02249     NULL,
02250     ff_h263_decode_end,
02251     ff_h263_decode_frame,
02252     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_FRAME_THREADS,
02253     .flush= ff_mpeg_flush,
02254     .max_lowres= 3,
02255     .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
02256     .pix_fmts= ff_hwaccel_pixfmt_list_420,
02257     .update_thread_context= ONLY_IF_THREADS_ENABLED(ff_mpeg_update_thread_context)
02258 };
02259 
02260 
02261 #if CONFIG_MPEG4_VDPAU_DECODER
02262 AVCodec ff_mpeg4_vdpau_decoder = {
02263     "mpeg4_vdpau",
02264     AVMEDIA_TYPE_VIDEO,
02265     CODEC_ID_MPEG4,
02266     sizeof(MpegEncContext),
02267     decode_init,
02268     NULL,
02269     ff_h263_decode_end,
02270     ff_h263_decode_frame,
02271     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_HWACCEL_VDPAU,
02272     .long_name= NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
02273     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_VDPAU_MPEG4, PIX_FMT_NONE},
02274 };
02275 #endif